Snap in place gasket for sealing plastic pipelines and method of installation

ABSTRACT

A pipe sealing gasket is shown which is designed to be received within a groove provided within a belled, socket end of a plastic pipe. The groove in the plastic pipe is preformed during manufacture and the gasket is installed thereafter. The gasket nominal diameter exceeds the internal diameter of the belled pipe end. A special installation tool is used to pull the gasket from an initially deformed, elliptical shape to a normal cylindrical shape. The installation tool uses only one fluid cylinder for power and can be hand installed and operated.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application claims priority from earlier filed provisionalapplication Ser. No. 60/616,463, filed Oct. 6, 2004, entitled “Snap InPlace Gasket for Sealing Plastic Pipelines and Method of Installation,”by Bradford G. Corbett, Jr.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to sealing gaskets and sealingsystems used for pipe joints in plastic pipelines in which a male spigotpipe section is installed within a mating female socket pipe section toform a pipe joint and, more specifically, to an improved gasket andinstallation method for installing a locked-in gasket within a preformedgasket groove in a section of pipe used to form a pipe joint.

2. Description of the Prior Art

Fluid sealing systems for plastic, fluid conveying pipes are used in avariety of industries. The pipes used in such systems are typicallyformed from thermoplastic materials including polyolefins and PVC. Informing a joint between sections of pipe, the spigot or male pipe end isinserted within the female or socket pipe end. An annular, elastomericring or gasket is typically seated within a groove formed in the socketend of the thermoplastic pipe. As the spigot is inserted within thesocket, the gasket provides the major seal capacity for the joint.Various types of sealing technologies have been employed to assure thesealing integrity of the pipe joint. It is important that the sealinggasket not be dislodged during the joint make up and that the gasket notbecome twisted or otherwise compromised in field applications.

In earlier gasketed sealing systems, the gasket was generallydeformable, allowing it to be flexed or bent by hand and inserted withina mating groove formed in the female, belled pipe end. One attempt toinsure the integrity of such pipe joints involved the use of a pipegasket having one region formed of an elastically yieldable sealingmaterial, such as rubber, and a second distinct region formed of a morerigid material, such as a rigid plastic. The rigid region of the gaskettended to hold the gasket in place within the pipe groove. Otherapproaches to the problem included the use of a homogeneous rubber ringwith a stiffening band which was manually inserted into a mating grooveprovided on the internal diameter of the rubber ring. In other words,the rubber ring was first flexed or bent and inserted into the groove inthe belled pipe end. The rigid retaining ring was then inserted into agroove in the rubber gasket ring. Each of these solutions was less thanideal, in some cases failing to provide the needed joint integrity andoften contributing to the complexity and expense of the manufacturingoperation.

In the early 1970's, a new technology was developed by Rieber & Son ofBergen, Norway, referred to in the industry as the “Rieber Joint.” TheRieber system employed a combined mould element and sealing ring forsealing a joint between the socket end and spigot end of two cooperatingpipes formed from thermoplastic materials. In the Rieber process, anelastomeric gasket was installed within an internal groove in the socketend of the female pipe as the female or belled end was simultaneouslybeing formed. Rather than utilizing a preformed groove, the Rieberprocess provided a prestressed and anchored elastomeric gasket duringthe belling operation. Because the gasket was installed simultaneouslywith the formation of the belled pipe end, a rigid, embedded reinforcingring could be supplied as a part of the gasket. Because the pipe groovewas, in a sense, formed around the gasket with its embedded reinforcingring, the gasket was securely retained in position and did not tend totwist or flip or otherwise allow impurities to enter the sealing zonesof the joint, thus increasing the reliability of the joint anddecreasing the risk of leaks or possible failure due to abrasion. TheRieber process is described in the following issued United Statespatents, among others: U.S. Pat. Nos. 4,120,521; 4,061,459; 4,030,872;3,965,715; 3,929,958; 3,887,992; 3,884,612; and 3,776,682.

Despite the advances offered by the Rieber process, the bellingoperation was somewhat complicated and costly. Also, certain situationsexist in which it would be desirable to install a gasket within apreformed groove in the selected pipe end, rather than utilizing anintegrally installed gasket in which the groove in the pipe is formedaround the gasket.

As mentioned above, in the prior art joints utilizing preformed grooves,gaskets were often provided in two parts. The main gasket body wasformed of an elastomeric material and typically featured an internalgroove or recess The main gasket body was first flexed by hand andinstalled within the groove provided in the belled pipe end. A hardenedband, formed of rigid plastic or metal, was then installed by handwithin the groove provided on the internal circumference of the gasket.While such retaining bands helped to resist axial forces acting on thegasket during assembly of the joint, the band could become displaced ortwisted during the insertion operation. It would therefore beadvantageous to be able to install a gasket of the type having anembedded reinforcing ring within a previously belled pipe end. However,gaskets with embedded reinforcing rings are not easily bent or flexed byhand, thus generally precluding hand assembly in the field. The size andposition of the embedded ring within the gasket body generally wasgreater than the diameter of the mouth opening of the belled pipe end,presenting a further complication for assembly.

U.S. Pat. No. 6,044,539, issued Apr. 4, 2000, to Guzowski, and commonlyowned by the present applicant describes a machine for inserting a“snap-fit” gasket having an embedded reinforcing ring into a preformedgasket receiving groove in a belled pipe end. However, such a machinewas fairly costly to construct and was not capable of being hand carriedby a worker in the field.

The present invention has, as one object, to provide an improved pipegasket for use in pipe joints which offers the advantage of a Riebertype locked-in seal while allowing the gasket to be installed in apreformed groove in snap-fit fashion, either at the manufacturing plantor in a field operation.

Another object of the invention is to provide an improved gasket whichis securely retained within a preformed pipe groove without thenecessity of a separate retaining band.

Another object of the invention is to provide an improved method ofinstalling a reinforced gasket within a preformed pipe groove.

Another object of the invention is to provide a method for installing agasket having a known external diameter within the mouth opening of abelled end of a pipe section where the external diameter of the gasketexceeds the internal diameter of the mouth opening of the pipe section.

Another object of the invention is to provide an improved gasketinstallation apparatus which is simpler and less costly than existingdevices and installation techniques.

SUMMARY OF THE INVENTION

A method is shown for installing a gasket within a gasket receivinggroove provided within the belled end of a plastic pipe section. Thebelled end has a mouth opening which is engageable with a spigot end ofa mating plastic pipe section to form a pipe joint. The pipe sectionhaving the belled end is first oriented along a horizontal work axis. Anannular gasket is then inserted within the mouth opening of the belledend. The annular gasket is oriented at an oblique angle with respect tothe horizontal work axis, whereby a leading edge is received in the pipegroove and a trailing edge of the annular gasket moves past the annulargroove provided in the belled end. A retracting force is then exerted onthe annular gasket by pulling the trailing edge thereof backwards in thedirection of the mouth opening of the belled end until the gasket snapsinto a locked-in position within the annular groove.

Preferably, the annular gasket has a body formed of a flexibleelastomeric material and has a relatively rigid ring which is located atan embedded location which circumscribes the gasket body. Preferably,the relatively rigid ring is made of steel and is generally round incross-section. The relatively rigid ring has an internal diameter whichdefines a locus of points which is equal to or greater than the internaldiameter of the remainder of the belled end of the pipe which joins theannular groove. The relatively rigid ring tends to resist axial forcestending to displace the gasket from the annular groove when in positionwithin the groove.

The gasket is preferably hand installed by means of an fluid pistonoperated installation tool. Once the gasket is initially positioned atan oblique angle within the belled pipe end, a mechanically operatedinsertion device is placed on the belled end of the plastic pipe. Theinsertion device is then actuated to thereby exert a retracting force onthe annular gasket by pulling the trailing edge thereof backwards instages in the direction of the mouth opening of the belled end until thegasket again assumes a generally cylindrical shape and snaps into alocked-in position within the annular groove.

The preferred installation tool has a mounting fixture which at leastpartially circumscribes the belled end of the pipe, the mounting fixturealso supporting an insertion guide and an associated retraction element.The mechanically operated insertion device is actuated to thereby exerta retracting force on the annular gasket by moving the retractionelement along a longitudinal axis of the insertion guide, therebypulling the trailing edge of the gasket backwards in stages in thedirection of the mouth opening of the belled pipe end. The longitudinalaxis of the positioning guide is oriented generally parallel to thehorizontal axis of the belled pipe end during use. The preferredmounting fixture has an associated fluid operated cylinder which can beselectively actuated to move the retraction element back and forth alongthe longitudinal axis of the positioning guide. The insertion apparatusfeatures a gripping handle which can be gripped by a user to handposition the apparatus on the belled pipe end.

An improved gasket is also shown for use with the installation tool. Thegasket has a gasket body formed of a flexible elastomeric material, thegasket body having a relatively rigid ring located at an embeddedlocation which circumscribes the gasket body. The relatively rigid ringis generally round in cross section and has a cross sectional diameterwhich defines a locus of points on an inner surface thereof which isequal to or greater than the internal diameter of the remainder of thebelled end of the pipe which joins the gasket receiving groove when thegasket is installed within the belled pipe end. Preferably, the gasketbody has a width to thickness ratio and wherein the ratio is greaterthan about 1.75:1.0. Most preferably, the width to thickness ratio isapproximately 2:1.

The preferred sealing gasket has an inner sealing surface which isprovided with a series of serrations thereon. The inner sealing surfaceis joined to a leading face which joins a convex nose region whichcontinues to form a primary sealing surface. The primary sealing surfacecomprises an evenly sloping outer face of the body and forms a lipregion thereof. The lip region is separated from a trailing face of thegasket body by means of a pair of convex regions which allow the lipregion to converge inwardly as the mating male spigot end of the matingpipe section encounters the primary sealing surface of the gasket.

Additional objects, features and advantages will be apparent in thewritten description which follows.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an end view of the insertion apparatus used to install thegasket of the invention within the preformed groove in the female,belled pipe end with portions of the insertion guide and retractionelement being shown in phantom lines.

FIG. 2 shows the first step in the installation method of the inventionin which the mounting fixture of the apparatus is placed onto thefemale, belled pipe end and a sealing gasket is placed within the belledpipe end with a leading edge of the gasket being positioned in theinternal pipe groove.

FIG. 2A is a view similar to FIG. 2 in which an insertion guide andassociated retraction element are fed axially along a horizontal workaxis of the belled pipe end.

FIG. 2B is a view similar to FIG. 2A but showing the retraction elementbeing used to pull up the trailing edge of the sealing gasket, causingthe gasket to be received in snap-fit fashion within the annular groovein the belled end of the pipe.

FIG. 3 is an isolated view of a portion of the insertion guide andassociated retraction element.

FIG. 4 is a simplified, schematic view, looking down on the retractionelement, showing the pivoting movement thereof.

FIG. 5 is a side, partial cross sectional view of the sealing gasket ofthe invention showing the location of the gasket reinforcing ring.

DETAILED DESCRIPTION OF THE INVENTION

Turning now to the attached illustrations, FIGS. 1 and 5 show the gasketof the invention and an installation apparatus used in the method of theinvention. The apparatus 11 (FIG. 1) is used to install a gasket (13 inFIG. 5) within a gasket receiving groove (15 in FIGS. 2 and 5) providedwithin the belled end 17 of a section of thermoplastic pipe 19. The pipesection 19 can be formed of any of a variety of commercially availablethermoplastic materials, such as the polyolefin family includingpolyethylene and polypropylene as well as polyvinyl chloride and similarmaterials. Thermoplastic pipes of this general type are used in avariety of industrial settings including water, sewage and chemicalindustries. The belled end 17 of the thermoplastic pipe section has amouth opening 21 (FIGS. 2 and 5) which is engageable with a spigot end(not shown) of a mating pipe section to form a pipe joint. The gasketreceiving groove 15 has been pre-formed in the pipe mouth opening 21 atthe manufacturing facility.

A particularly preferred gasket 13 which can be used in the method ofthe invention is shown in cross-section in FIG. 5. Preferably, thegasket 13 is an annular, ring-shaped member formed of a flexibleelastomeric material, such as a suitable rubber. As will be apparentfrom FIG. 5, the gasket 13 has an external diameter “d₁” which isgreater than the internal diameter “d₂” of the mouth opening of thebelled end of the pipe. The elastomeric material used to form the body23 of the gasket will vary in composition depending upon the endapplication but may include natural and synthetic rubbers including, forexample, SBR, EPDM, NBR, nitrile rubber, etc. In the embodiment of thegasket shown in FIG. 5, the gasket includes an inner sealing surface 25which, in this case, is provided with a series of ribs or serrations 27.The gasket includes a leading face 29 which joins a convex nose region31 which continues on to form a primary sealing surface 33. In thiscase, the primary sealing surface 33 is an evenly sloping, outer face ofthe body 23 which forms a lip region 35 thereof. The lip region isseparated from a trailing face 37 of the gasket body by means of convexregions 39, 41 which allows the lip region 35 to “flap” inwardly as themating male, spigot end of a mating pipe section encounters the primarysealing surface 33 of the gasket and pushes the lip region 35 in thedirection of the surface 41.

The gasket body 23 also has a relatively rigid ring 43 embedded thereinhaving a midpoint 44. The relatively rigid ring 43 can be made of avariety of relatively rigid materials, including hard plastics andcomposites, but is preferably made of steel. The relatively rigid ringis generally round in cross-section, as shown in FIG. 5, andcircumscribes the annular body 23 of the gasket 13 at one embedded,circumferential location.

The positioning of the relatively rigid ring within the gasket body iscritical to the method of the invention. The axis 45 in FIG. 1 passesthrough the approximate mid-point 47 of the gasket body 13. Therelatively rigid ring 43 is located in front of the vertical axis 45 asviewed along the longitudinal axis of the pipe 46 in a location adjacentthe convex nose region 31. The relatively rigid ring 43 also has across-sectional diameter (“d₃” in FIG. 5) and an internal diameter whichdefines a locus of points (e.g., point 51) which is equal to or greaterthan the internal diameter (“d₂” in FIG. 5) of the belled end 17 of thepipe which joins the annular groove 15. In other words, if a point 51 onthe inner surface of the ring 43 is one point in the locus of points, animaginary line 53 drawn tangent to the point 51 is approximately at theinternal diameter “d₂” of the pipe or is located further inward in thedirection of the bottom surface 55 of the groove 15.

The cross section of the gasket 13 shown in FIG. 5 has light anddarkened regions which are intended to represent recommended regions forplacement of the rigid ring 43. The ring 43 can be located in any regionof the gasket body shown in FIG. 5 other than the darkened regions.However, the most preferred location is forward of the axis 45 in thedirection of the nose region 31, as shown in FIG. 5. Most preferably,the ring 43 is located forward of the axis 48 in FIG. 5 and adjacent thenose region 31. This places the ring 43 in the forward quarter of themass of the rubber of the gasket body.

The relatively rigid ring 43 of the annular gasket tends to resist axialforces tending to displace the gasket from the annular groove 15 when inposition within the groove. To position the ring 43 at a location withinthe gasket body 23 so that it resides partly or wholly within the groove15 would appear to pose a problem, since the ring diameter then exceedsthe nominal pipe diameter “d₂”. The method and installation device ofthe invention provide a convenient mechanism for installing the gasketwithin the preformed pipe groove, even with a relatively rigid ringwhose ultimate internal diameter equals or exceeds the internal diameterof the remainder of the pipe.

Turning now to FIGS. 1-4, the installation device and method ofinstallation of the improved gasket of the invention will be describedin greater detail. As shown in FIG. 1, the mechanical insertionapparatus 11 includes a mounting fixture 61. The mounting fixture 61 hasa spaced apart, arcuate inner portion 63 and outer portion 65. Thearcuate inner portion 63 has a semi-cylindrical lip 64 which is sized tobe closely received within the mouth opening 21 of the belled pipe end17. The lip 64 is slightly tapered, as shown in FIG. 1, to assist itsinsertion within the pipe mouth opening. The lip 64 and mounting fixture61 both locate the installation device and provide a mechanical assistin cooperation with a rod-like positioning guide 67 and an associatedretraction element 69 to locate the gasket in “snap-fit” fashion.

The positioning guide 67 is attached to the mounting fixture so as toextend along the pipe horizontal axis (46 in FIG. 5) when in use. Theguide has an outer longitudinal extent (68 in FIG. 1) which convenientlyserves as a handle which can be grasped by a user in order to handposition the entire apparatus onto the mouth opening of the belled pipeend. The retraction element 69 (shown in isolated fashion in FIGS. 3 and4) has an upper extent 71 with a cross bore 73 which rides along thelength of that portion of the positioning guide 67 which is opposite thehandle portion 68. The retraction element 69 is also connected to theoutput shaft 75 of a fluid cylinder 77 (in this case a pneumaticcylinder). Application of pneumatic pressure from a suitable fluidsource (not shown) serves to extend and retract the retraction elementalong the horizontal work axis. In the preferred installation method ofthe invention, only one pneumatic cylinder 77 is used to pull the gasket13 into the pipe groove 15 in three steps, as will be described ingreater detail.

The lowermost extent 78 of the retraction element terminates in a wedgeshaped scraper 80 which physically contacts the sealing gasket in orderto urge the gasket into position within the internal groove provided inthe belled pipe end. The wedge shaped scraper 80 has an arcuate lowerprofile 82 which allows it to travel smoothly along the internaldiameter of the pipe mouth opening. The wedge shaped scraper is alsofree to pivot about a vertical axis (90 in FIG. 4) in order to contactthe gasket evenly.

The operation of the mechanical operated insertion apparatus 11 will nowbe described. In the first step of the method, illustrated in simplifiedfashion in FIG. 2, the gasket 13 is first inserted within the mouthopening 21 of the belled pipe end. Because the diameter of the gasket isgreater than the diameter of the pipe end opening, it is necessary toorient the gasket at an oblique angle with respect to the horizontalaxis of the pipe. This allows the gasket to be inserted within the pipemouth opening and allows the upper region of the gasket to be pulledinto position in registry with the upper region of the pipe groove. Themovement of the gasket from a near horizontal position to an obliqueangle is indicated in phantom lines in FIG. 2.

The mechanically operated insertion device is then actuated to exert aretracting force on the annular gasket by moving the retraction element69 along a longitudinal axis of the insertion guide, thereby pulling thetrailing edge of the gasket backwards in stages in the direction of themouth opening of the belled pipe end until the gasket again assumes agenerally cylindrical shape and snaps into a locked in position withinthe annular groove.

FIGS. 2A and 2B shown the gasket 13 being grasped by the scraper 80 andpulled into locked-in position within the pipe groove 15. However, thepneumatic cylinder of the hand operated installation apparatus ispreferably actuated in a three step sequence, as follows: (1) theretraction element is used to grip and pull up the lower left side ofthe gasket; (2) the retraction element is used to grip and pull up thelower right side of the gasket; and (3) finally, the retraction elementis used to grip and pull up the center portion of the gasket until thegasket “snaps” into position in snap fit fashion within the gasketreceiving groove of the belled pipe end. The longitudinal axis of thepositioning guide (92 in FIGS. 2A and 2B) is oriented generally parallelto the horizontal axis (46 in FIG. 5) of the belled pipe end during theinsertion operation. The gripping handle 68 of the device allows aworker to grip and support the apparatus on the belled pipe end, eitherat a factory location, or in a field installation.

An invention has been provided with several advantages. The method forinstalling a gasket of the invention allows a pipe gasket to beinstalled within a preexisting and preformed groove in a thermoplasticpipe. Once the gasket has been locked into position in snap-fit fashion,it is securely retained within the pipe groove and resists axial forcestending to displace the gasket from the annular groove. Because a gasketis inserted within a preformed pipe groove, the manufacturing andinstallation processes are simplified and made less costly. The gasketwhich is utilized in the process is simple in design and economical tomanufacture and does not require exotic materials or multiplecomponents. There is no need for an external retaining band to assist insecuring the gasket within the pipe groove. The gasket of the inventionis retained so securely within the pipe groove that it would generallybe necessary to destroy the pipe material to remove the gasket once thegasket is in locked-in position.

The mechanical insertion apparatus is simple in design and economical tomanufacture. The device utilizes only one fluid operated cylinder andthus is extremely dependable in operation. The device is relativelylight weight and can be easily lifted and positioned by a worker in amanufacturing plant or in a field location.

While the invention has been shown in only one of its forms, it is notthus limited but is susceptible to various changes and modificationswithout departing from the spirit thereof.

1. A method for installing a gasket with an embedded reinforcing ringwithin a gasket receiving groove provided within the belled end of aplastic pipe section, the belled end having a mouth opening which isengageable with a spigot end of a mating plastic pipe section to form apipe joint, the method comprising the steps of: providing a plastic pipesection having a preformed belled end opening; orienting the pipesection having the belled end along a horizontal work axis; temporarilypositioning an annular gasket within the mouth opening of the belledend, the gasket being temporarily transformed from a generallycylindrical shape to a generally elliptical shape and being oriented atan oblique angle with respect to the horizontal work axis such that aleading edge of the gasket engages the annular groove and such that atrailing edge of the annular gasket is moved past the annular grooveprovided in the belled end; hand positioning a mechanically operatedinsertion device on the belled end of the plastic pipe; actuating themechanically operated insertion device to thereby exert a retractingforce on the annular gasket by pulling the trailing edge thereofbackwards in stages in the direction of the mouth opening of the belledend until the gasket again assumes a generally cylindrical shape andsnaps into a locked-in position within the annular groove.
 2. The methodof claim 1, wherein the mechanically operated insertion device includesan insertion guide, an associated retraction element and a source offluid power for moving the retraction element along a longitudinal axisof the insertion guide.
 3. The method of claim 2, wherein the insertiondevice carries a fluid cylinder which is operatively associated with theretraction element for moving the retraction element back and forthalong the longitudinal axis of the insertion guide.
 4. The method ofclaim 3, wherein the insertion device pulls the trailing edge of thegasket backward in a three step operation in the direction of the mouthopening of the belled end to thereby cause the gasket to be received insnap-fit fashion within the annular groove.
 5. The method of claim 1,wherein the pipe sections are formed of a synthetic plastic materialselected from the group consisting of polypropylene, polyethylene andpolyvinyl chloride.
 6. The method of claim 1, wherein the annular gasketis inserted within the mouth opening of the belled end of the pipesection at an angle less than 90 degrees with respect to the horizontalworking axis of the belled end.
 7. The method of claim 1, wherein theannular gasket has a body formed of a flexible elastomeric material andwherein the embedded reinforcing ring comprises a relatively rigid ringlocated at an embedded location which circumscribes the gasket body, therelatively rigid ring being generally round in cross-section.
 8. Themethod of claim 7, wherein the relatively rigid ring is made of amaterial selected from the group consisting of metal, hard rubber, rigidplastics and composites.
 9. The method of claim 8 wherein the relativelyrigid ring is made of steel.
 10. The method of claim 7, wherein therelatively rigid ring has a cross-sectional diameter which defines alocus of points on an inner surface thereof which is equal to or greaterthan the internal diameter of the remainder of the belled end of thepipe which joins the annular groove.
 11. A method for installing agasket with an embedded reinforcing ring within a gasket receivinggroove provided within the belled end of a plastic pipe section, thebelled end having a mouth opening which is engageable with a spigot endof a mating plastic pipe section to form a pipe joint, the methodcomprising the steps of: providing a plastic pipe section having apreformed belled end opening; orienting the pipe section having thebelled end along a horizontal work axis; temporarily positioning anannular gasket within the mouth opening of the belled end, the gasketbeing temporarily transformed from a generally cylindrical shape to agenerally elliptical shape and being oriented at an oblique angle withrespect to the horizontal work axis such that a leading edge of thegasket engages the annular groove and such that a trailing edge of theannular gasket is moved past the annular groove provided in the belledend; positioning a mechanically operated insertion device on the belledend of the plastic pipe, the insertion device having a mounting fixturewhich at least partially circumscribes the belled end of the pipe, themounting fixture also supporting an insertion guide and an associatedretraction element; actuating the mechanically operated insertion deviceto thereby exert a retracting force on the annular gasket by moving theretraction element along a longitudinal axis of the insertion guide,thereby pulling the trailing edge of the gasket backwards in stages inthe direction of the mouth opening of the belled end until the gasketagain assumes a generally cylindrical shape and snaps into a locked-inposition within the annular groove.
 12. The method of claim 11, whereinthe longitudinal axis of the positioning guide is oriented generallyparallel to the horizontal axis of the belled pipe end.
 13. The methodof claim 12, wherein the mounting fixture has an associated fluidoperated cylinder which can be selectively actuated to move theretraction element back and forth along the longitudinal axis of thepositioning guide.
 14. The method of claim 13, wherein the insertionapparatus features a gripping handle which can be gripped by a user tohand position the apparatus on the belled pipe end.
 15. The method ofclaim 14, wherein the gasket has a body formed of a flexible elastomericmaterial and wherein the embedded reinforcing ring comprises arelatively rigid ring located at an embedded location whichcircumscribes the gasket body, the relatively rigid ring being generallyround in cross section, the relatively rigid ring having a crosssectional diameter which defines a locus of points on an inner surfacethereof which is equal to or greater than the internal diameter of theremainder of the belled end of the pipe which joins the gasket receivinggroove.
 16. A gasket for installation within a gasket receiving grooveprovided within the belled end of a plastic pipe section, the belled endhaving a mouth opening which is engageable with a spigot end of a matingplastic pipe section to form a pipe joint, the gasket comprising: agasket body formed of a flexible elastomeric material, the gasket bodyhaving a relatively rigid ring located at an embedded location whichcircumscribes the gasket body, the relatively rigid ring being generallyround in cross section, the relatively rigid ring having a crosssectional diameter which defines a locus of points on an inner surfacethereof which is equal to or greater than the internal diameter of theremainder of the belled end of the pipe which joins the gasket receivinggroove when the gasket is installed within the belled pipe end.
 17. Thegasket of claim 16, wherein the gasket body has a width to thicknessratio and wherein the ration is greater than about 1.75:1.0.
 18. Thegasket of claim 17, wherein the width to thickness ratio isapproximately 2:1.
 19. The gasket of claim 16, wherein the gasket bodyhas an inner sealing surface which is provided with a series ofserrations thereon, the inner sealing surface being joined to a leadingface which joins a convex nose region which continues to form a primarysealing surface, the primary sealing surface comprising an evenlysloping outer face of the body and which forms a lip region thereof, thelip region being separated from a trailing face of the gasket body bymeans of a pair of convex regions which allow the lip region to convergeinwardly as the mating male spigot end of the mating pipe sectionencounters the primary sealing surface of the gasket.